Cycloaddition of 6-hydroxy-2,6-dimethylcyclohexa-2,4-dienones with ethyl vinyl ether, butyl vinyl ether, vinyl acetate and vinyl phenyl sulphone leading to a stereoselective entry into bicyclo[2.2.2]octanes having quaternary methyl group is reported. A novel thermal 1,2-methyl migration has also been described.